The present invention relates to a semiconductor device, and particularly relates to effective techniques applicable to a semiconductor device formed by mounting a semiconductor chip on one surface of a wiring board via a bump electrode and provided with a package structure in which resin is filled in a gap area between the one surface of the above wiring board and the principal surface of the above semiconductor chip.
A semiconductor device, formed by mounting a semiconductor chip on one surface of a wiring board via a bump electrode, and provided with a package structure in which resin is filled in a gap area between the one surface of the wiring board and the principal surface of the semiconductor chip, is developed as described on pages 14 to 19 of the April issue of Electronic Material published in 1996 by Industrial Research Association, for example. As the mechanical strength of the resin filled in the gap area between the one surface of the wiring board and the principal surface of the semiconductor chip can compensate that of the bump electrode in this semiconductor device, the bump electrode can be prevented from being damaged due to the difference in thermal expansion coefficient between the wiring board and the semiconductor chip. As the rear surface (opposite to the principal surface of the semiconductor chip) and the side face are exposed in this semiconductor device and the area in which the semiconductor chip is exposed to the air is large, the efficiency of heat radiation in which heat generated from the semiconductor chip is radiated in the air is higher, compared with a semiconductor device in which the semiconductor chip is sealed in a seal box, and compared with a semiconductor device which is mounted in a cavity formed by a package.